Mainly used to explain a characteristic trait of Irish Men. This is used to explain the charming way in which they approach others, especially women. It ranges from a pleasant smile, twinkle in their bright (often bright green or blue) eyes, or being chivalrous and pleasant in tone and body language.
"a man's irish charm could win over any lass"
"Arriving from Ireland, Carr joins Michael’s criminal world and uses his good looks and Irish charm to get what he wants, using merciless violence when things don’t go his way."
"it's hard to stay upset at a man with so much irish charm"